In some wireless communication systems, a user equipment (UE) wirelessly communicates with a base station to send data to the base station and/or receive data from the base station. A wireless communication from a UE to a base station is referred to as an uplink communication, and a wireless communication from a base station to a UE is referred to as a downlink communication.
Resources are required to perform uplink and downlink communications. For example, a UE may wirelessly transmit data to a base station in an uplink transmission at a particular frequency and/or during a particular slot in time. The frequency and time slot used are examples of resources.
In some wireless communication systems, if a UE is to transmit data to a base station, the UE requests uplink resources from the base station. The base station grants the uplink resources, and then the UE sends the uplink transmission using the granted uplink resources. An example of uplink resources that may be granted by the base station is a set of time/frequency locations in an uplink orthogonal frequency-division multiple access (OFDMA) frame.
Channel coding, such as forward error-correction coding or error-correction coding, introduces redundancy into a signal prior to transmission or storage of the signal. The redundancy enables a receiving system to detect and, in some cases, correct errors introduced into the signal by, for example, the channel, the receiver, the transmitter, a storage medium, and the like. For example, in a communication system that employs forward error-correction coding, a source provides data to an encoder (also referred to as a coder). The encoder inserts redundant (also sometimes referred to as parity) bits, thereby outputting a longer sequence of coded bits, called a codeword. Codewords can then be transmitted to a receiver, which uses a suitable decoder to extract the original, unencoded data and may also correct errors caused by, for example, the channel and/or the receiver.
Channel coding can thus be used to detect and/or correct errors—reducing the need for the source transmitter to retransmit data that was not successfully decoded. By reducing the need to retransmit data that is not successfully decoded, the throughput of the channel or link is improved.
In the current LTE design, a transport block (TB) can be divided into several forward error correction (FEC) blocks, and these FEC blocks will be scheduled by the scheduler. H-ARQ retransmission, however, is TB based to reduce the complexity of network devices by limiting the number of concurrent H-ARQ processes to 8. If the decoding of one FEC block within a TB transmission fails (via cyclic redundancy code (CRC) check), the redundant versions of all the FEC blocks will have to be retransmitted, even though some of the FEC blocks may have been correctly decoded.
In fifth-generation (5G) wireless communications, major communication scenarios include eMBB (enhanced Mobile Broadband), mMTC (massive Machine Type Communications) and URLLC (Ultra-Reliable and Low Latency Communications). A core requirement of mMTC is to provide massive service connectivity with low energy consumption and low cost. In URLLC, extreme requirements on transmission availability and reliability are emphasized, which means low error probability and low outage rate are main targets. For eMBB, high system capacity, high data rate, and high spectrum efficiency are main targets.
It has been envisioned that there may be different frame structure designs for different usage scenarios. For instance, a short transmission time interval has been identified as a way to meet the latency target for URLLC. Considering the diverse usage scenarios of the 5 G air interface, also known as new radio (NR), it is possible to have one deployment covering multiple scenarios. For example, an evolved Node B (eNB) or a gNodeB (gNB) may need to support eMBB and URLLC services at the same time. In another example, an eMBB eNB may have multiple neighbor cells providing URLLC service. However, supporting the desired levels of service could be challenging due to the burst interference caused by such coexistence of different usage scenarios. Short transmission of URLLC packets may appear as bursty interference to an eMBB transmission, for example. In the coexistence of eMBB and URLLC, the bursty interference may erase a portion of a transmission and hence cause a code block to be uncorrectable even at high signal to noise ratio (SNR). The failed decoding of such a coding block (CB) leads to a decoding failure of the whole TB.